1. Field of the Invention
This invention relates to brake actuators for bicycles, and related pedal operated vehicles.
2. Review of the Art
My U.S. Pat. No. 4,313,530 issued Feb. 2, 1982 describes a brake actuator for bicycles which has proven quite satisfactory in practice. It enables an effective, durable and relatively easily manufactured clutch to be accommodated within the space available in the pedal crank housing in the bottom bracket of typical bicycles. Two problems remain in the implementation of the invention. Firstly, typical mass produced pedal crankshafts are not designed to carry such a clutch, and typically have a waisted centre portion between the bearing races. This entails either using a custom forged crankshaft or building up the diameter of the central portion of the shaft by some form of metal deposition process. Both solutions are expensive. Secondly, even with the spring structure of the invention, the length of the spring required is such as to be a close fit within the available space. The longer the spring, the more turns it has and the more difficult it becomes to maintain concentricity of the turns during manufacture and assembly. A reduction in the number of turns in the spring would be a substantial advantage if it could be achieved.